The use of cationic antimicrobial agents to reduce plaque and gingivitis has been recognized for many years. Included among references disclosing, such compositions are U.S. Pat. No. 3,937,805, Feb. 10, 1976 to Harrison; U.S. Pat. No. 3,937,807, Feb. 10, 1976 to Haefele; U.S. Pat. No. 4,080,441, Mar. 21, 1978 to Gaffar et al.; U.S. Pat. No. 4,118,474, Oct. 3, 1978 to Gaffar et al.; U.S. Pat. No. 4,241,049, Dec. 23, 1980 to Colodney et al.; U.S. Pat. No. 3,925,543, Dec. 9, 1975 to Donohue; U.S. Pat. No. 4,256,731, Mar. 17, 1981 to Curtis et al.; U.S. Pat. No. 4,217,342, Aug. 12, 1980 to Gaffar; U.S. Pat. No. 4,259,316, Mar. 31, 1981 to Nakashima et al.; U.S. Pat. No. 4,309,409, Jan. 4, 1982 to Coll-Palagos et al.; and U.S. Pat. No. 4,169,885, Oct. 2, 1979 to Raaf et al. In addition lozenges containing cationic antimicrobials have been sold and the patents to Curtis et al. and Raaf et al. disclose lozenges but not of the type of the present invention.
Plaque is a term commonly used to describe the colonization and growth of microorganisms on both the surface and subsurface regions of the teeth. Antimicrobials have been shown to be able to interrupt this cycle and thereby reduce the level of plaque formed but have oftentimes caused unacceptable levels of staining. Maintaining a high level of efficacy and acceptable staining has proven to be difficult to achieve.
It has now been found with the present lozenges that concentration of the antimicrobial in the mouth as the lozenge dissolves can be minimized without compromising the level of active in saliva after dissolution of the lozenge, which is therapeutically effective against plaque and gingivitis.
It is therefore an object of the present invention to formulate effective antiplaque/antigingivitis compositions. By reducing plaque, caries may also be reduced.
It is a further object of the present invention to formulate antiplaque/antigingivitis compositions which have reduced staining.
These and other objects will become more apparent from the detailed description which follows. All percentages and ratios herein are by weight unless otherwise specified.